Need some advice - What would be a good pleco/bottom cleaner for a 75 gallon?

I will be getting it from Petsmart or Big Al's so, nothing too pricy or out of the way to get.

I personally like plecos and have several different species but purchasing them as "cleaner fish" is perhaps not wise if one consider's the amount of waste (poop) they create on daily basis. This result's in more waste to be removed with weekly water change rather than providing a cleaner substrate.
With that said , I would maybe select a species that does not get too large = less poop.
Bristlenose would be my first choice for they stay relatively small (5 inches), and are fairly easy to find .

Agree. It is hard to second guess what you might mean by "cleaner," since some fish are useful for picking up bits of food, no fish can exist on this but requires proper balanced nutrition suited to the species. And no fish will "clean" the substrate. Snails are better at this, along with plants and regular maintenance by the aquarist.

Corydoras and loaches (those species that remain suitable in size for a group in a 75g) are interesting fish that also help with substrate food, and some pleco species in for instance the genus Hypancistrus remain under 5-6 inches and are primarily carnivorous (i.e., not algae grazers like Bristlenose species).

Several of these are in our profiles, second tab from the left in the blue bar across the top, under catfish (cory species, pleco) and Cyprinids (loaches).

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

Sorry, by cleaner I meant something that will eat any extra food on the bottom, and algae. I currently have a type of pleco that does this in my 30 gal (forgot the name at the moment)... but he is pretty small and I would like something bigger in the 75 gal. Extra poop I can handle, as I do gravel vacuums weekly and change the water.

Sorry, by cleaner I meant something that will eat any extra food on the bottom, and algae. I currently have a type of pleco that does this in my 30 gal (forgot the name at the moment)... but he is pretty small and I would like something bigger in the 75 gal. Extra poop I can handle, as I do gravel vacuums weekly and change the water.

Would small catfish work as well?

I am not to familier with plecos, so bear with me :)

Thanks.

No problem. What type of algae? All of the so-called algae-eating fish are fairly restrictive in the type ofalgae they will eat. Most catfish will not touch algae, at least not in any significant amount.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

No problem. What type of algae? All of the so-called algae-eating fish are fairly restrictive in the type ofalgae they will eat. Most catfish will not touch algae, at least not in any significant amount.

Err... I really have no idea what kind of algae. Whatever kind grows on gravel and glass I guess.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]